The present invention relates to magnetic modules and to processes for manufacturing magnetic modules. More particularly, the present invention relates to reduced volume, light weight, low profile, planar magnetic modules for integrated magnetic circuitry and processes for manufacturing such magnetic modules.
In the field of electronic circuit design and manufacture, significant effort has been devoted to the miniaturization and planarization of components and circuitry. These efforts have resulted in the continued reduction in the size of consumer, commercial and military electronic and power electronic systems.
One area in which these efforts have been frustrated is in the design of circuits utilizing magnetic components. Traditionally, magnetic components, such as inductors and transformers, have been built as discrete devices for incorporation onto printed circuits boards. These magnetic components are comparatively large, near cube shaped, devices which do not easily conform to the printed circuit layout. The use of these devices has resulted in a lowering of volumetric packaging efficiency and has set limits on the efforts at miniaturization.
The use of discrete magnetic components has also resulted in a reduction of the overall cost efficiency of integrated circuit manufacture. Typically, the discrete magnetic components are fabricated by separate manufacturers resulting in a duplication of design and manufacturing resources and thus limiting cost effectiveness.
A need, therefore, currently exists for a process for manufacturing planar, low profile, highly efficient integrated magnetic components which are compatible with integrated circuits. Particularly, recent developments in very high speed integrated circuits (VHSIC) have led to a requirement for reduced volume, high efficiency, high power density, low profile, low voltage, reliable electronic power converters operating at frequencies in excess of 1 Megahertz. At present, the best available commercial low voltage power converter volume exceeds that occupied by all of the electronic components in VHSIC circuitry.
Current techniques for fabricating ferrite core shapes for magnetic components require component core machining which is a cumbersome process that degrades the properties of the magnetic cores and wastes material. A need, therefore, also exists for a process that is capable of forming various magnetic core shapes without the need for component core machining.
The present invention satisfies, to a great extent, the need for planar, low profile, highly efficient integrated magnetic components which are compatible with integrated circuitry. This result is achieved by providing a magnetic module having a magnetic core plasma sprayed onto a substrate board.
The magnetic core may be plasma sprayed into a cavity etched in a substrate die. The plasma sprayed magnetic core may be low or high permeability, ultra low loss substituted nickel zinc cobalt (NiZnCo) or manganese zinc cobalt (MnZnCo) ferrites. These magnetic cores are deposited onto the patterned regions of the non-magnetic module and the other regions serve as winding windows, inductor air gaps, isolations or as a mounting substrate for other system components.
In another aspect of the present invention a magnetic module is provided having a plurality of magnetic cores plasma sprayed into cavities patterned in a non-magnetic substrate die. The substrate die can be patterned using laser ablation, ion milling or mechanical machining. The substrate die may be a composite of graphite, alumina or other similar non-magnetic material.
In its process aspects, the present invention is achieved by a process for manufacturing magnetic modules wherein magnetic material is plasma sprayed onto a substrate board to form a magnetic core. The magnetic material may be plasma sprayed into a cavity patterned into the substrate die.
In another aspect of the present invention a process for manufacturing magnetic modules is provided wherein magnetic material is plasma sprayed into a plurality of cavities patterned into a substrate die to form a plurality of magnetic cores. The magnetic material may be substituted nickel zinc cobalt ferrites or substituted manganese zinc cobalt ferrites. The process may also include patterning the substrate board, which may be a composite of graphite, a composite of alumina or other non-magnetic ceramic, using ion milling, laser ablation or mechanical machining.
It is an object of the present invention to reduce the overall manufacturing cost, size and weight of electronic or power electronic systems by fabricating all the magnetic components of a power converter on a single monolithic plate using a single fabrication process of plasma spraying.
It is a further object of the present invention to provide magnetic modules having highly efficient, high power density magnetic components which have reduced volume and low profile.
It is yet another object of the present invention to provide a process for manufacturing magnetic modules having highly efficient, high power density magnetic components which have reduced volume and low profile.
With these and other objects, advantages and features of the invention that may become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims and to the several drawings attached herein.